Valve for door-checks.



No. 811,830. PATENTBD FEB. 6, 1906. N. W. URANDALL. VALVE-FOR DOOR CHECKS.

UNITED STATES PATENT OFFICE.

NATHAN W. CRANDALL, OF NEW BRlTAlN, CONNECTICUT, ASSIGNOR TO RUSSELL & ERVVIN lVlANUFACTURlNG COMPANY, OF NEW BRITAIN, CONNECTICUT, A CORPORATION OF CONNEC"1CUT.

VALVE FOR DOOR-CHECKS.

Specification of Lotters'Patent.

Patented Feb. 6, 1906.

To all whom it away concern- Be it known that I, NATIIANW. CRANDALL, a citizen of the United States, residing at New Britain, in the county of Hartford, State of Connecticut, have invented certain new and useful lrn rovements in Valves for Door- Ohecks, of which the following is a full, clear, and exact description.

My invention relates to improvements in liquid door-checks, and has particular reference to the valve mechanism whereby the speed of travel of the iston may he controlled and varied at will In the drawings, Figure 1 is a view, partly in vertical section and partly in elevation, of a. check provided with my improvement. Fig. 2 is a cross-section of the piston-cylinder on the plane of the line 2 2 of Fig. I. Fig. 3 is an end elevation of the iston-cylinder. Fig. 4 is a horizontal sections. view of the piston and cylinder. Fig. 5 is an end view of the valve for the iston. Fig. 6 is an end view of the piston etached. Fig. 7 is a section of a ortion of the piston, taken on the plane oft e line 7 7 of Fig. 6.

The spring mechanism, if any is provided, is immateria to this invention.

1 is a cylinder.

2 is a piston of any suitable form having the piston-head 2. 3 is a rotatable spindle. 3 is a crank thereon. 4 is a connecting-rod between said piston and said crank.

In the end of the cylinder 1 is so ported a plug 5, which is preferably of angu or crosssection, as shown, with its inner end tapered. This plug passes through a valve 6 in the form of a plate or washer arranged to bear against the seat at the outside of the pistonhead .2. when the piston moves back. This valve 6 has a hub-like portion 6, which passes through the cylinder-head and is preferably of suitable shape to approximately though loosely lit the lug 5 Between the hub 6 of the valve an the side of the opening in the piston-head through which it passes there 1s sufficient space to allow of the free hackfiow of liquid contained within the cylinder 1 when the piston moves toward the spindle 3. The inner end or ends of the hub 6* are offset, as at 6*, to prevent the entire disenga ement of the valve from the piston: head. hese offset portions 6* are spaced apart sufiiciently from the inside of the piston-head to enable the valve proper to become unseated from the piston-head when the piston advances, thus allowing the said free bacliilow. To one side of the passage in the piston-head there is a comparatively small port 2". In the valve 6 there is also a coinparativel small port 6. These ports 2 and 6 are preferably of substantially the same size, so that when they register the liquid contained between the end of the c' linder and the outer end of the piston-head wiil flow through the said ports to allow the piston to be moved back, although not without some resistance.

2 is a groove or channel cut in the outer face of the piston-head 2, the said groove bein concentric and gradually increasing in depth from its shallowest end to its deepest end, the latter end communicating with the port 2*. (See Fig. 6.)

From the foregoing it will be seen that if the valve 6 is turned so that the port 6 will overstand a portion of the groove 2 the liquid will flow through the ports 2* 6 with less freedom than if the ports 2* and 6 registered. This is true because the groove is of less cross sectional area than said ports. As the crosssectional area oi the groove decreases it is obvious that by shifting the angular position of the valve relatively to the piston the freedom of flow of liquid through the iston 2 as it moves toward the adjacent end of the cylinder may be increased or diminished at will. This shiftin of the valve 6 may be controlled by turning i. re plug 5, and this maybe accomplished by having the handle portion or finger 7 connected to the end of the lug 5 and arranged outside and at the end of the cylinder.

To provide a free closing movement of the door at any particular position, the end por tion of the plug 5 may be tapered or cut away at its sides or corners, as shown in the drawings, to permit the free passage of liquid hack throu h the piston-head between the sides of said p ug and the surrounding walls or bore of the o ositc portion 6 of the valve.

It wiil he seen that the port 2 is an auxiliary port, as is also the port 6. These ports operate only when the piston is performing its checking function or moving toward the adjacent end of the cylinder under the influence of the spindle rotated by the closing door. It is obvious that these auxiliary ports,

as well as the valve and its mountings, may be varied in many ways without departing from the spirit or scope of this invention.

What I claim is- 1. In a liquid door-check, a piston having a passage through its head and an auxiliary passage adjacent thereto, a valve having a hub thereon projecting through said passage in said piston-head and having a port arranged to register with said auxiliary passage through said head and a plug mounted in the check-case and engaging with said valve whereby the angular position of the lat ter may be varied to increase or diminish-the cross-sectional area of the fluid-passage formed by the said auxiliary passage and the port in said valve.

2. In a liquid door-check, a piston provided with a passage through its head and having an auxiliary port therein, an open valve-body loosely seated in said passage and constructed to take a flat seat a ainst the front face of the piston-head and to automatically open when the piston is moved in one direction, and to automatically close when the piston is moved in the opposite direction, said valve-body having a port located to register with the auxiliary port of the piston-head, and means to vary the operative position of the valve for the purpose described.

3. In a liquid door-check, a piston, a valve loosely mounted in the head of said piston and arranged to bear flatwise against an outer seat thereon when the piston is moved in one direction and to become freed from said seat when the piston moves in an opposite direction, an auxiliary li uid-passage throu h said valve and piston head, means for adjusting said valve by rotation to increase or diminish the cross-sectional area of said auxiliary passage.

4. In a liquid door-check, a piston, a valve loosely mounted in the head of said piston and arranged to bear flatwise against an outer seat thereon when the piston is moved in one direction and to become freed from said seat when the piston moves in an opposite direction, an auxiliary liquid passage through said valve and piston-head, means for adjusting said valve to increase or diminish the cross-sectional area of said auxiliary passage, said means comprising a rotatable plug carried by the check-casing and engagmg said valve but non-rotatable independently thereof.

5. In a liquid door-check, a piston, a main passage and an auxiliary passa e through the pistonhead, a valve for both o said assages comprising a platelooselyheld bysai pistonhead and overstanding said auxiliary passage and a rotatable plug loosely fitting said plate and cooperating therewith, and a port in said plate arranged to register with said auxiliary passage.

6. In a liquid doorcheck, a piston having a main and an auxiliary passage through its head and a concentric groove of graduallydecreasing cross sectional area extending from said auxiliary port to the surface of the head, a valve for both of said passages comprising a plate loosely held by said head and overstanding said auxiliary passage, a rotatable plug loosely fitting said plate, the latter having a port arranged to register with said auxiliary passage, and means for adjusting said rotatable plug to change the operative position of said valve.

Signed at New Britain, Connecticut, this 28th day of Se tember, 1904.

ATHAN W. CRANDALL. Witnesses M. S. VVIARI), F. E. SUNBURN. 

